In my experience early event stages weren't hard to complete, they were hard to get three medals on. The very first stage of the very first event (Lavender's) has two random panels between your squads and a pest fight, meaning each squad has to flip a coin twice and hope for the 'right' outcome in order to fight those pests and thus get all three medals. Mind you, this was back when events gated the Knight's skill level and equipment slots behind how many medals you collected, so anything less than 24 medals (a 'perfect' clear of all eight stages) meant Lavender wouldn't have all four equipment slots along with a level five skill.
There were also stages like the 80 stamina stage in the first half of Edelweiss' event, a hot mess with multiple instances of a random movement tile standing between your squads and a pest fight. Guess how many medals were required back then for a 5/4 Edelweiss? :P